Have questions about C4 Corvette suspensions for your Tri5? Ask them here!

[rockytopper R.I.P 5-13-2017]

Front or rear? Early or late C4?

either and both front and back.

[Custer55]

What size wheels and or tires and what wheel offset works with the C4 setup in a trifive?

I have been running the stock 90 Corvette wheels and tires on mine for a while now with no clearance issues at all. I have the late C4 set up. Fronts are 9.5 x 17 wheels with 56mm offset, Rears are 17 x 9.5 wheels with 56mm offset plus a 3/16" spacer which makes it a 51mm offset with the spacer. Tires all the way around are 275/40/17 (stock size for the 90 Vette) I think a 285 tire would be fine in back. In the front I will probably eventually go to a 255 tire just to lower the front of the car a bit. Not sure if this would work on any C4 conversion but it is working on mine.
Brian

[chevynut]

I have the late C4 set up. Fronts are 9.5 x 17 wheels with 56mm offset, Rears are 17 x 9.5 wheels with 56mm offset plus a 3/16" spacer which makes it a 51mm offset with the spacer. Tires all the way around are 275/40/17:

Custer per my calculations your front tires are 68.4" across and I'm surprised they don't rub. Most guys start having problems at around or a little over 68" but that's with stock suspension geometry and steering. The c4 setup turns differently and not as far. Yours is a 55 so you have more room too. Have you turned sharply with the suspension compressed like driving into a steep driveway? How much did you drop the front from stock?

Maybe 68" to 68.5" works fine with the c4 setup since yours seems to work. How close are you tires to the frame at full lock?

[chevynut]

What size wheels and or tires and what wheel offset works with the C4 setup in a trifive?

In the rear a 275 tire works without mini tubs with the limiter being the tubs at 46.5" wide. You actually have about 12.5" to work with in the wheel well. You might squeeze a 285 in there but it would be pretty tight. Once you minitub it the dog bones become the limiter and you can go 295 or possibly 305 depending on how tight you want the clearances. You can go really close to the dogbone. To go any bigger you'd have to narrow the rearend which you can't do much without narrowing the frame. I think you can get away on the big end with a 55 nomad with the big wheel openings.

[Custer55]

Custer per my calculations your front tires are 68.4" across and I'm surprised they don't rub. Most guys start having problems at around or a little over 68" but that's with stock suspension geometry and steering. The c4 setup turns differently and not as far. Yours is a 55 so you have more room too. Have you turned sharply with the suspension compressed like driving into a steep driveway? How much did you drop the front from stock?

Maybe 68" to 68.5" works fine with the c4 setup since yours seems to work. How close are you tires to the frame at full lock?

My suspension drop is about 3" The frame is 4" off the ground at the kick up at the firewall. I try not to go to fast in and out of drive ways and angle through them if there steep. At full lock there isn't much clearance to the tire at the fender or the frame, maybe 1/4" to 1/2", but like I said I have not had anything rubbing to this point. The C4 suspension design may be the reason it works as I had rubbing issues with the stock suspension with McGaughys 2" drop spindles at the top of the fender opening with 235 tires on the front on sharp turns at 15 to 20 mph.
Brian

[rockytopper R.I.P 5-13-2017]

OK thanks. Cluster pretty much answered my question. I ask this because every trifive C4 conversion I've found pictures of are running corvette wheels. The 2 inch back spacing required explains why. The C4 conversion pretty much forces a pro-touring look there aren't any old school wheels of any width that would work giving the front spacing is more or less 3.25 inches if cluster is close to the max envelope.

Rocky

[NickP]

Who's Cluster? LOL

[chevynut]

I ask this because every trifive C4 conversion I've found pictures of are running corvette wheels. The 2 inch back spacing required explains why.

All you really needed to see that is the suspension widths. The early ones are 61" front 62" rear. The late ones are 1" wider. And you don't have to use Corvette wheels. Any wheel with the right offset works. Wade's nomad pictured on my website has a late front end and Boyd's wheels.

The C4 conversion pretty much forces a pro-touring look there aren't any old school wheels of any width that would work

Why would anyone want "old school " wheels on a C4 conversion?😳 Again, ANY wheel with the right offset will work. An early C4 setup can handle about 1/2" less offset.

[rockytopper R.I.P 5-13-2017]

[QUOTE=chevynut;35155]All you really needed to see that is the suspension widths. The early ones are 61" front 62" rear. The late ones are 1" wider. And you don't have to use Corvette wheels. Any wheel with the right offset works. Wade's nomad pictured on my website has a late front end and Boyd's wheels.

I'm not implying 15 inch lol, I stand corrected the earlier version does give room to not have a flat faced wheel that's all I mean. The 57 on your site is a prime example.

[chevynut]

Wade's blue nomad has the wider late front end with an early rear. I think the wheels look great.

A lot of guys have the misconception that you have to use corvette wheels.

We built a frame earlier this year that's planned to use stock 15" steel wheels and white walls.

My nomad has a stock tri5 width (60") narrowed late C4 rear.